US5986284A - Semiconductor device - Google Patents
Semiconductor device Download PDFInfo
- Publication number
- US5986284A US5986284A US09/064,867 US6486798A US5986284A US 5986284 A US5986284 A US 5986284A US 6486798 A US6486798 A US 6486798A US 5986284 A US5986284 A US 5986284A
- Authority
- US
- United States
- Prior art keywords
- wiring layer
- protective wiring
- integrated circuit
- semiconductor device
- protective
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
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Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L23/00—Details of semiconductor or other solid state devices
- H01L23/57—Protection from inspection, reverse engineering or tampering
- H01L23/573—Protection from inspection, reverse engineering or tampering using passive means
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L23/00—Details of semiconductor or other solid state devices
- H01L23/552—Protection against radiation, e.g. light or electromagnetic waves
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
- H01L2924/0001—Technical content checked by a classifier
- H01L2924/0002—Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S257/00—Active solid-state devices, e.g. transistors, solid-state diodes
- Y10S257/922—Active solid-state devices, e.g. transistors, solid-state diodes with means to prevent inspection of or tampering with an integrated circuit, e.g. "smart card", anti-tamper
Definitions
- the present invention relates to a semiconductor device constituted by a semiconductor chip having a protective wiring layer on an integrated circuit.
- EEPROMS electrically erasable programmable read only memories
- a basic cell of a conventional EEPROM has a structure shown in FIG. 4.
- a source 303 and a drain 304 are formed at a predetermined interval in a region defined by a field oxide film 302 on a p-type semiconductor substrate 301.
- a floating gate 306 electrically insulated from surroundings is formed through a gate insulating film 305 on the semiconductor substrate 301 and the drain 304 between the source 303 and the drain 304.
- a control gate 308 is formed on the floating gate 306 through an insulating film 307.
- the floating gate 306 and the control gate 308 are made of heavily doped polysilicon.
- Reference numeral 309 denotes an insulating film formed on the field oxide film 302 and the control gate 308.
- part of the gate insulating film 305 between the floating gate 306 and the drain 304 is formed as thin as about 10 nm.
- a data erase when the control gate 308 is applied with a positive voltage much higher than a voltage to the drain 304, electrons enter the floating gate 306 from the drain 304.
- a data write by changing the polarity of the voltage applied to the control gate 108, the electrons within the floating gate 306 are removed to the drain 304. The electron flow passes through the thin gate insulating film 305 by a tunnel phenomenon.
- the EEPROM is advantageous in that data can be electrically written/erased in/from individual memory cells.
- data stored in the EEPROM is naturally erased by irradiation of ultraviolet rays.
- FIG. 5 shows a semiconductor chip having such a light-shielding film.
- An ultraviolet-shielding layer 403 is formed every memory cell in the region of an EEPROM 402 on a semiconductor chip 401 on which an integrated circuit is formed.
- the ultraviolet-shielding layer 403 is only formed in the region of the EEPROM 402. If the ultraviolet-shielding layer 403 is damaged due to any reason, the damage to the layer 403 is not recognized until it is externally observed. Accordingly, the reliability of stored data cannot be assured.
- the ultraviolet-shielding layer 403 is damaged, an EEPROM cell is irradiated with ultraviolet rays through this damaged region to damage the stored data.
- the damage to the ultraviolet-shielding layer 403 can be recognized by externally observing the semiconductor chip having an integrated circuit made up of the EEPROM 402. When, however, the semiconductor chip is incorporated in a data communication device or the like, the state of the EEPROM 402 cannot be always externally observed.
- the damage to the ultraviolet-shielding layer 403 may lead to damage or disconnection of an upper wiring layer constituting the EEPROM 402. Also in this case, the damage cannot be detected, and the device may malfunction owing to a defective semiconductor chip.
- a semiconductor device comprising a semiconductor chip on which at least one integrated circuit is formed, a protective wiring layer formed to be spread on the integrated circuit at a very small interval, and made of a conductive light-shielding material, the protective wiring layer being applied with a power supply voltage upon operating the integrated circuit, and abnormality detecting means for monitoring the voltage applied to the protective wiring layer and outputting an abnormality detection signal when the monitored voltage is an abnormal voltage.
- FIG. 1A is a view schematically showing a semiconductor device according to an embodiment of the present invention.
- FIG. 1B is a sectional view of the main part of an EEPROM shown in FIG. 1A;
- FIG. 2 is a circuit diagram of a fault detector and a fault state memory unit shown in FIG. 1A;
- FIGS. 3A and 3B are plan views each showing another example of a protective wiring layer
- FIG. 4 is a sectional view showing part of a conventional EEPROM cell.
- FIG. 5 is a plan view of a semiconductor chip showing the state wherein a light-shielding film is formed on a conventional EEPROM.
- FIG. 1A schematically shows a semiconductor device according to an embodiment of the present invention.
- an EEPROM 2 and a random circuit 3 are formed as integrated circuits on a semiconductor chip 1.
- Conductive light-shielding protective wiring layers 4a and 4b made of Al are respectively formed on the EEPROM 2 and the random circuit 3.
- the material constituting the protective wiring layers 4a and 4b is not limited to Al, and another conductive light-shielding metal material such as Cu or Ti may also be used.
- each of the protective wiring layers 4a and 4b is connected to a power supply VDD, and the other end is connected to ground 6 through a corresponding one of resistors 5a and 5b.
- the protective wiring layers 4a and 4b have predetermined widths and are formed on the EEPROM 2 and the random circuit 3 such that adjacent wires are spread in a zigzag shape at a very small interval without contacting each other. That is, the protective wiring layers 4a and 4b function as light-shielding films covering predetermined regions corresponding to the EEPROM 2 and the random circuit 3. This structure prevents light from entering a portion below the covered region.
- a fault detector 7 is connected to the protective wiring layers 4a and 4b between the EEPROM 2 and the resistor 5a and between the random circuit 3 and the resistor 5b.
- a fault state memory unit 8 is connected to the fault detector 7 to store an output from the fault detector 7.
- FIG. 1B shows the main part of the EEPROM 2 in FIG. 1A.
- a source 103 and a drain 104 are formed at a predetermined interval in a region defined by a field oxide film 102 on a p-type semiconductor substrate 101.
- a floating gate 106 electrically insulated from surroundings is formed through a gate insulating film 105 on the semiconductor substrate and the drain between the source 103 and the drain 104.
- a control gate 108 is formed on the floating gate 106 and the field oxide film 102 through an insulating film 107.
- the floating gate 106 and the control gate 108 are made of heavily doped polysilicon.
- the protective wiring layer 4a shown in FIG. 1B is formed on the semiconductor substrate 101 including the control electrode 108 through interlevel insulating films 109 and 110.
- the protective wiring layer 4a is formed to have a small interval determined by the interlevel insulating film 110 so as to prevent adjacent interconnections from contacting each other.
- part of the gate insulating film 105 between the floating gate 106 and the drain 104 is formed as thin as about 10 nm.
- a data erase when the control gate 108 is applied with a positive voltage much higher than a voltage to the drain 104, electrons enter the floating gate 106 from the drain 104 in the region of the thin gate insulating film 105.
- a data write by changing the polarity of the voltage applied to the control gate 108, the electrons within the floating gate 106 are removed to the drain 104.
- a power supply voltage VDD is kept applied to the protective wiring layers 4a and 4b, and the potentials of the protective wiring layers 4a and 4b are kept at potentials (normal potentials) defined by the resistors 5a and 5b.
- VDD voltage
- the potentials of the protective wiring layers 4a and 4b are kept at potentials (normal potentials) defined by the resistors 5a and 5b.
- the fault detector 7 monitors the potential on one end side of each of the resistors 5a and 5b, and upon detecting the abnormal potential at even one end side, outputs an fault (abnormality) detection signal.
- the fault detection signal output from the fault detector 7 is stored in the fault state memory unit 8.
- the protective wiring layers 4a and 4b protect the EEPROM 2 and the random circuit 3 from irradiation of light (ultraviolet rays). Therefore, in, e.g., the EEPROM 2, stored data can be protected from being erased by irradiation of light (ultraviolet rays).
- the protective wiring layer 4a or 4b can be detected without externally observing the semiconductor device that the protective wiring layer 4a or 4b is damaged, and an abnormality has occurred in stored data by irradiation of light through the damaged portion. That is, if the protective wiring layer 4a or 4b is damaged, a fault detection signal is output from the fault detector 7 and stored in the fault state memory unit 8. By checking the memory contents of the fault state memory unit 8, an abnormality in stored data can be detected.
- FIG. 2 shows the fault detector 7 and the fault state memory unit 8.
- the fault detector 7 is constituted by inverters 71 and 72 for respectively inverting input signals from the protective wiring layers 4a and 4b, and an OR circuit 73 for ORing outputs from the inverters 71 and 72.
- the fault state memory unit 8 is constituted by a flip-flop 81.
- the OR circuit 73 receives two "L"-level inputs. Accordingly, the OR circuit 73 outputs an "L”-level signal, and the flip-flop 81 holds the "L”-level signal. To the contrary, if either of the protective wiring layers 4a and 4b is disconnected, either of two inputs to the OR circuit 73 changes to "H” level. Then, the OR circuit 73 outputs an "H"-level signal, and the flip-flop 81 holds the "H"-level signal.
- the semiconductor device in FIG. 1A may be formed not to operate when the output from the flip-flop 81 is at "H" level.
- a reset circuit 9 may be connected to the output stage of the flip-flop 81, and the semiconductor device in FIG. 1A may be initialized when the output from the flip-flop is at "H" level. That is, upon detection of a data abnormality in the semiconductor device, the use of the defective semiconductor device is disabled. With this arrangement, a device incorporating the defective semiconductor device can be prevented from malfunctioning.
- the above embodiment has exemplified the case wherein the protective wiring layer constituting the light-shielding film is formed in a zigzag shape.
- the present invention is not limited to this, and a protective wiring layer 201 may be formed into a rectangular spiral shape, as shown in FIG. 3A.
- the other end 202 of the protective wiring layer must be extracted from the central portion of the protective wiring layer 201 through an insulating film.
- a protective wiring layer 203 may be formed in a lattice or reticulate shape with a structure of two wiring layers in directions perpendicular to each other.
- the protective wiring layer 203 is obtained by connecting, through a contact 203c, a lower protective wiring layer 203a and a protective wiring layer 203b formed above the lower protective wiring layer 203a through an insulating film.
- the protective wiring layer 203 can further improve light-shielding properties.
- the protective wiring layer having light-shielding properties is spread at a very small interval in a predetermined region on a semiconductor chip, the state wherein a data abnormality has occurred by irradiation of light on the integrated circuit owing to the damage to the protective wiring layer can be electrically detected.
Abstract
Description
Claims (20)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP9104531A JP3037191B2 (en) | 1997-04-22 | 1997-04-22 | Semiconductor device |
JP9-104531 | 1997-04-22 |
Publications (1)
Publication Number | Publication Date |
---|---|
US5986284A true US5986284A (en) | 1999-11-16 |
Family
ID=14383084
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US09/064,867 Expired - Lifetime US5986284A (en) | 1997-04-22 | 1998-04-22 | Semiconductor device |
Country Status (6)
Country | Link |
---|---|
US (1) | US5986284A (en) |
EP (1) | EP0874401B1 (en) |
JP (1) | JP3037191B2 (en) |
KR (1) | KR100281206B1 (en) |
CN (1) | CN1157787C (en) |
DE (1) | DE69830867T2 (en) |
Cited By (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20040104754A1 (en) * | 2002-11-29 | 2004-06-03 | Rainer Bruchhaus | Radiation protection in integrated circuits |
US20040140508A1 (en) * | 2003-01-14 | 2004-07-22 | Matsushita Electric Industrial Co., Ltd. | Semiconductor device and method for fabricating the same |
US20050050507A1 (en) * | 2003-08-28 | 2005-03-03 | Matsushita Electric Industrial Co., Ltd | Basic cell, edge cell, wiring shape, wiring method, and shield wiring structure |
US20050047047A1 (en) * | 2003-08-28 | 2005-03-03 | Matsushita Electric Industrial Co., Ltd. | Protection circuit for semiconductor device and semiconductor device including the same |
US20050051351A1 (en) * | 2001-11-28 | 2005-03-10 | De Jongh Petra Elisabeth | Semiconductor device, card, system, and methods of initializing and checking the authenticity and the identify of the semiconductor device |
US6879340B1 (en) * | 1998-08-19 | 2005-04-12 | Micron Technology Inc. | CMOS imager with integrated non-volatile memory |
US20060055044A1 (en) * | 2004-09-10 | 2006-03-16 | Kimihiro Maemura | Semiconductor device |
US20060184807A1 (en) * | 1999-09-02 | 2006-08-17 | Kocher Paul C | Specialized circuitry for cryptographic authentication and other purposes |
US20060180939A1 (en) * | 2005-02-16 | 2006-08-17 | Matsushita Electric Industrial Co., Ltd. | Tamper-resistant semiconductor device |
Families Citing this family (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2801999A1 (en) * | 1999-12-01 | 2001-06-08 | Gemplus Card Int | Smart card with integrated circuit chips includes additional conductive mesh providing protection against fraudulent access to chips |
JP4212255B2 (en) * | 2001-03-30 | 2009-01-21 | 株式会社東芝 | Semiconductor package |
DE10140045B4 (en) * | 2001-08-16 | 2006-05-04 | Infineon Technologies Ag | IC chip with protective structure |
CN100365786C (en) * | 2002-12-31 | 2008-01-30 | 上海贝岭股份有限公司 | Detecting method of silicon material quality in dielectrode integrated circuit |
EP1968112A3 (en) * | 2003-02-04 | 2008-09-17 | Matsushita Electric Industrial Co., Ltd. | Semiconductor integrated circuit device |
FR2864667B1 (en) * | 2003-12-29 | 2006-02-24 | Commissariat Energie Atomique | PROTECTING AN INTEGRATED CIRCUIT CHIP CONTAINING CONFIDENTIAL DATA |
CN202855734U (en) * | 2012-10-23 | 2013-04-03 | 北京同方微电子有限公司 | Active protector used for intelligent card |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
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JPH0538915A (en) * | 1991-02-13 | 1993-02-19 | Atsugi Unisia Corp | Electromagnetic suspension device |
US5663574A (en) * | 1994-09-29 | 1997-09-02 | Siemens Aktiengesellchaft | Power semiconductor component with monolithically integrated sensor arrangement as well as manufacture and employment thereof |
US5864501A (en) * | 1996-11-04 | 1999-01-26 | Hyundai Electronics Industries Co., Ltd. | Test pattern structure for endurance test of a flash memory device |
US5889410A (en) * | 1996-05-22 | 1999-03-30 | International Business Machines Corporation | Floating gate interlevel defect monitor and method |
Family Cites Families (5)
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JPS5856355A (en) * | 1981-09-30 | 1983-04-04 | Hitachi Ltd | Semiconductor integrated circuit device |
US4519050A (en) * | 1982-06-17 | 1985-05-21 | Intel Corporation | Radiation shield for an integrated circuit memory with redundant elements |
JPS62143476A (en) * | 1985-12-18 | 1987-06-26 | Fujitsu Ltd | Semiconductor storage device |
JPH0691176B2 (en) * | 1989-12-07 | 1994-11-14 | 株式会社東芝 | High power semiconductor device |
US5818095A (en) * | 1992-08-11 | 1998-10-06 | Texas Instruments Incorporated | High-yield spatial light modulator with light blocking layer |
-
1997
- 1997-04-22 JP JP9104531A patent/JP3037191B2/en not_active Expired - Fee Related
-
1998
- 1998-04-21 KR KR1019980014189A patent/KR100281206B1/en not_active IP Right Cessation
- 1998-04-22 DE DE69830867T patent/DE69830867T2/en not_active Expired - Fee Related
- 1998-04-22 CN CNB981074588A patent/CN1157787C/en not_active Expired - Fee Related
- 1998-04-22 EP EP98107308A patent/EP0874401B1/en not_active Expired - Lifetime
- 1998-04-22 US US09/064,867 patent/US5986284A/en not_active Expired - Lifetime
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
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JPH0538915A (en) * | 1991-02-13 | 1993-02-19 | Atsugi Unisia Corp | Electromagnetic suspension device |
US5663574A (en) * | 1994-09-29 | 1997-09-02 | Siemens Aktiengesellchaft | Power semiconductor component with monolithically integrated sensor arrangement as well as manufacture and employment thereof |
US5889410A (en) * | 1996-05-22 | 1999-03-30 | International Business Machines Corporation | Floating gate interlevel defect monitor and method |
US5864501A (en) * | 1996-11-04 | 1999-01-26 | Hyundai Electronics Industries Co., Ltd. | Test pattern structure for endurance test of a flash memory device |
Cited By (30)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20050112792A1 (en) * | 1998-08-19 | 2005-05-26 | Micron Technology, Inc. | CMOS imager with integrated non-volatile memory |
US8384814B2 (en) | 1998-08-19 | 2013-02-26 | Micron Technology, Inc. | CMOS imager with integrated circuitry |
US8089542B2 (en) | 1998-08-19 | 2012-01-03 | Micron Technology, Inc. | CMOS imager with integrated circuitry |
US6879340B1 (en) * | 1998-08-19 | 2005-04-12 | Micron Technology Inc. | CMOS imager with integrated non-volatile memory |
US7569414B2 (en) | 1998-08-19 | 2009-08-04 | Micron Technology, Inc. | CMOS imager with integrated non-volatile memory |
US20110228153A1 (en) * | 1998-08-19 | 2011-09-22 | Chevallier Christophe J | Cmos imager with integrated circuitry |
US7952631B2 (en) | 1998-08-19 | 2011-05-31 | Micron Technology, Inc. | CMOS imager with integrated circuitry |
US20090284623A1 (en) * | 1998-08-19 | 2009-11-19 | Chevallier Christophe J | Cmos imager with integrated non-volatile memory |
US9569628B2 (en) | 1999-09-02 | 2017-02-14 | Cryptography Research, Inc. | Specialized circuitry for cryptographic authentication and other purposes |
US20060184807A1 (en) * | 1999-09-02 | 2006-08-17 | Kocher Paul C | Specialized circuitry for cryptographic authentication and other purposes |
US20050051351A1 (en) * | 2001-11-28 | 2005-03-10 | De Jongh Petra Elisabeth | Semiconductor device, card, system, and methods of initializing and checking the authenticity and the identify of the semiconductor device |
US6940111B2 (en) | 2002-11-29 | 2005-09-06 | Infineon Technologies Aktiengesellschaft | Radiation protection in integrated circuits |
US20040104754A1 (en) * | 2002-11-29 | 2004-06-03 | Rainer Bruchhaus | Radiation protection in integrated circuits |
US20090206454A1 (en) * | 2003-01-14 | 2009-08-20 | Matsushita Electric Industrial Co., Ltd. | Semiconductor device and method for fabricating the same |
US7851891B2 (en) | 2003-01-14 | 2010-12-14 | Panasonic Corporation | Semiconductor device and method for fabricating the same |
US20040140508A1 (en) * | 2003-01-14 | 2004-07-22 | Matsushita Electric Industrial Co., Ltd. | Semiconductor device and method for fabricating the same |
US7194719B2 (en) | 2003-08-28 | 2007-03-20 | Matsushita Electric Industrial Co., Ltd. | Basic cell, edge cell, wiring shape, wiring method, and shield wiring structure |
US20050047047A1 (en) * | 2003-08-28 | 2005-03-03 | Matsushita Electric Industrial Co., Ltd. | Protection circuit for semiconductor device and semiconductor device including the same |
US7376928B2 (en) | 2003-08-28 | 2008-05-20 | Matsushita Electric Industrial Co., Ltd. | Basic cell, edge cell, wiring shape, wiring method, and shield wiring structure |
US20070257683A1 (en) * | 2003-08-28 | 2007-11-08 | Matsushita Electric Industrial Co., Ltd. | Protection circuit for semiconductor device and semiconductor device including the same |
US7256599B2 (en) | 2003-08-28 | 2007-08-14 | Matsushita Electric Industrial Co., Ltd. | Protection circuit for semiconductor device and semiconductor device including the same |
US20070162884A1 (en) * | 2003-08-28 | 2007-07-12 | Matsushita Electric Industrial Co., Ltd. | Basic cell, edge cell, wiring shape, wiring method, and shield wiring structure |
US20050050507A1 (en) * | 2003-08-28 | 2005-03-03 | Matsushita Electric Industrial Co., Ltd | Basic cell, edge cell, wiring shape, wiring method, and shield wiring structure |
US7345497B2 (en) | 2003-08-28 | 2008-03-18 | Matsushita Electric Industrial Co., Ltd. | Protection circuit for semiconductor device and semiconductor device including the same |
CN101320720B (en) * | 2004-09-10 | 2010-06-16 | 精工爱普生株式会社 | Semiconductor device |
US20060055044A1 (en) * | 2004-09-10 | 2006-03-16 | Kimihiro Maemura | Semiconductor device |
US20080012141A1 (en) * | 2004-09-10 | 2008-01-17 | Kimihiro Maemura | Semiconductor device |
US7285817B2 (en) | 2004-09-10 | 2007-10-23 | Seiko Epson Corporation | Semiconductor device |
US20060180939A1 (en) * | 2005-02-16 | 2006-08-17 | Matsushita Electric Industrial Co., Ltd. | Tamper-resistant semiconductor device |
US7547973B2 (en) * | 2005-02-16 | 2009-06-16 | Panasonic Corporation | Tamper-resistant semiconductor device |
Also Published As
Publication number | Publication date |
---|---|
EP0874401A3 (en) | 1999-10-27 |
DE69830867T2 (en) | 2006-04-20 |
CN1201259A (en) | 1998-12-09 |
EP0874401A2 (en) | 1998-10-28 |
KR100281206B1 (en) | 2001-02-01 |
JPH10294444A (en) | 1998-11-04 |
KR19980081584A (en) | 1998-11-25 |
EP0874401B1 (en) | 2005-07-20 |
DE69830867D1 (en) | 2005-08-25 |
JP3037191B2 (en) | 2000-04-24 |
CN1157787C (en) | 2004-07-14 |
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